Information retrieval and display systems are known having browsing facilities whereby, for example, lists of items, such as news articles, available from a data storage apparatus may be browsed through and a particular item on the list selected and displayed.
Conventional browsing systems are based on a "point and click" approach. That is, the user must move a cursor on the display, for example by moving a mouse, to position the cursor at a predefined point on the display, and then generate a control signal by "clicking" with the mouse to cause a predefined operation to occur. More particularly, the conventional system involves the display on a screen of a list of items which are available, and browsing through that list is achieved by moving a mouse so as to cause a cursor displayed on the screen to move to a predefined icon on the screen, and then clicking on the icon so that a different part of the list is displayed on the screen. To view a desired article, the user must again move the mouse so as to cause the cursor to move to the title of the desired article, and then click on the article so that the article itself is displayed on the screen.
This approach is both cumbersome to use and relatively slow. In particular, the technique requires the user to perform at least two actions to change the information displayed--firstly an action to move the cursor to the required point on the screen, which can typically require the user to move the cursor across the whole length of the screen, and secondly an action to "click" at the point on the screen to cause a predetermined operation to be performed. Further, the technique requires accurate hand-eye co-ordination, since it requires the user to accurately manipulate the mouse to move the cursor to the exact position required on the screen before the clicking operation can be performed. A further problem lies in the fact that the user must know where to point and click in order to perform the required command. For example, the user must know which icon to click on in order to scroll forwards in a display, and which different icon to click on to scroll backwards in the display, and must also know where to click once an article is being viewed in order to return to the main list of articles so that a further article can be selected. In addition, many repeated user actions can be required to scroll through a lengthy source of information.
In other conventional systems, the point and click environment is not provided, and instead the user is required to type in commands in order to control the displayed information. This compounds the problems above, in particular in that a plurality of operator actions are required to perform a command, and the user must know what commands to type.